BTH Electric Boilers
USE & CARE MANUAL
(Revision August /06)
, Page
22.
Operation
Before operating this boiler, be sure to read
and follow these instructions, as well as the
warnings printed in this manual. Failure to
do so can result in unsafe operation of the
boiler resulting in property damage, bodily
injury, or death. Should you have any
problems reading, following or difficulty in
understanding the instructions in this
manual, STOP, and get help from a qualified
person.
Do not turn on the boiler unless it is filled
with water. Do not turn on the boiler if the
cold water supply shut-off valve is closed.
After the boiler has been plumbed and wired, it
is now ready to be set for automatic operation.
FILLING THE BOILER
Open the shutoff valve (and on a zone valve
system, manually open zone valve) on the
supply piping from the boiler. Open cold water
supply valve (fill or makeup water valve) to
boiler.
To let the air out of the boiler tank during the fill
process open the relief valve on top of the
boiler. Leave all shutoff valves open. Return
zone valves to automatic operation. Check
system for leaks and repair. Purge air from the
remaining zones, if necessary. Check boiler
pressure gage reading. 15 to 20 psi is normal for
most installations.
ADJUSTING THE AQUASTATS
After the system has been manually purged of
air, and all components (valves, vents,
controllers) have been set properly, the boiler
can be started. Never operate this boiler until
this has been done.
Safety and energy conservation are factors to be
considered when setting the boiler water
temperature by using the aquastats. The most
energy efficient operation will result when the
temperature setting of each aquastat is the
lowest that satisfies the needs consistent with
the application.
Please refer to the BWTD
table for more details.
Each electric element has it own aquastat.
Set the temperature on the aquastat using the
knob graduated in degrees Celsius and
Fahrenheit.
Set the temperature on the first aquastat to the
highest supply temperature required by the
heating system.
Set the temperature on the second aquastat
from 1°F to 20°F below the setpoint of the first
aquastat. Usually 5°F below the setpoint of the
first aquastat is adequate if the boiler water
temperature drop is 20°F.
Proceed in a similar manner for the 3
rd
, 4
th
and
any supplementary aquastats, lowering the set
point by 5°F each time. The elements will thus
be activated (and de-activated) in the number
required by the set points and the drop (or rise)
in boiler water temperature.
On initial start up (on the first day of the heating
season) with a cold tank, a considerable amount
of time may be required for the tank to reach
desired temperature. Check the temperature on
the boiler temperature gage.
Adjust the boiler aquastats as needed. Note that
setting the aquastat to a lower setting will not
have an immediate effect. The stored boiler
water heat will first have to be consumed.
Additional checks of the water temperature
should follow completion of a cycle. Further
adjustments may be necessary as you use your
boiler and space heating system.
Note:
The maximum setting for the boiler water
supply to the heating system is 190°F.
SAFETY PRECAUTIONS
!
